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J. Roeleveld wrote: |
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> On Thu, March 24, 2011 12:30 pm, Volker Armin Hemmann wrote: |
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> |
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>> On Thursday 24 March 2011 08:49:52 J. Roeleveld wrote: |
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>> |
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>>> On Wed, March 23, 2011 5:43 pm, Volker Armin Hemmann wrote: |
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>>> |
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>>>> md raid devices can do barriers. Don't know about lvm. But lvm is such |
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>>>> |
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>>> a |
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>>> |
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>>>> can |
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>>>> of worms I am surprised people still recommend it. |
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>>>> |
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>>> What is wrong with LVM? |
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>>> I've been using it successfully without any issues for years now. |
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>>> It does what it says on the box. |
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>>> |
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>> it is another layer that can go wrong. Why take the risk? There |
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>> are enough cases of breakage after upgrades - and besides snapshots... is |
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>> the |
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>> amount of additional code running really worth it? Especially with bind |
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>> mounting? |
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>> |
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> There are always things that can go wrong and I agree, adding additional |
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> layers can increase the risk. |
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> However, the benefits of easily and quickly changing the size of |
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> partitions and creating snapshots for the use of backups are a big enough |
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> benefit to off-set the risk. |
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> |
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> Bind-mounting is ok, if you use a single filesystem for everything. I have |
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> partitions that are filled with thousands of small files and partitions |
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> filled with files are are, on average, at 1GB in size. |
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> I haven't found a filesystem yet that successfully handles both of these |
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> with identical performance. |
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> When I first tested performance I found that a simple "ls" in a partition |
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> would appear to just hang. This caused performance issues with my |
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> IMAP-server. |
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> I switched to a filesystem that better handles large amounts of small |
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> files and performance increased significantly. |
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> |
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> The way I do backups is that I stop the services, create snapshots and |
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> then restart the services. |
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> I then have plenty of time to backup the snapshot. |
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> If I were to do this differently, I'd end up having a downtime for over an |
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> hour just for a backup. |
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> Now, it's barely a minute of downtime. |
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> |
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> That, to me, is a very big bonus. |
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> |
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> -- |
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> Joost |
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> |
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> |
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|
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I have never used LVM but when it messes up after a upgrade, as has |
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happened to many others, see if you say the same thing. I hope your |
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backups are good and they can restore. |
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|
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Dale |
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|
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:-) :-) |
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